USEPA has updated its rules about how small municipal separate storm sewer systems (MS4) obtain coverage under National Pollutant Discharge Elimination System (NPDES) general permits. The final MS4 General Permit Remand Rule aims to promote greater public engagement through clear requirements on the opportunities for public participation in the permitting process.

The updated rule establishes two alternative approaches an NPDES permitting authority can use to issue and administer small MS4 general permits that address a partial remand of the Phase II stormwater regulations by the Ninth Circuit U.S. Court of Appeals. Both approaches ensure that the permitting authority establishes what is necessary for the MS4 to “reduce the discharge of pollutants from the MS4 to the maximum extent practicable, to protect water quality, and to satisfy the appropriate water quality requirements of the Clean Water Act,” referred to as the “MS4 permit standard,” and that the public participation requirements of the Clean Water Act (CWA) are met.

To access additional information, including a fact sheet, about USEPA's Final MS4 General Permit Remand Rule, click here.